C# winform 向数据库里添加信息

//向系统日志表里添加记录
            DataBase.con.Open();
            using (OracleCommand comm = new OracleCommand("insert into t_syslog"+"values(@opr_type_code,@opr_type_value,@syslog_cont,@ip_address,@opr_user_id,@syslog_date)", DataBase.con))
            {
                comm.Parameters.Add("@opr_type_code", OracleType.VarChar,100, "opr_type_code").Value = 2;
                comm.Parameters.Add("@opr_type_value", OracleType.Int32, 5, "opr_type_value").Value = 8;
                comm.Parameters.Add("@syslog_cont", OracleType.VarChar, 4000, "syslog_cont").Value = "用户" + eName + "于" + DateTime.Now + "通过客户端登录";
                comm.Parameters.Add("@ip_address", OracleType.VarChar, 30, "ip_address").Value = AddressIP;
                comm.Parameters.Add("@opr_user_id", OracleType.Int32, 5, "opr_user_id").Value = eID;
                comm.Parameters.Add("@syslog_date", OracleType.DateTime, 20, "syslog_date").Value = DateTime.Now;
                comm.ExecuteNonQuery();
                comm.Dispose();
            }
            DataBase.con.Close();
运行时报错，显示当前上下文中不存在名称“comm”